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So ass we know the gen 1 battery pack for 2014 has I believe a 10.7 usable size of the batter to get the 38 miles at least rated. So today in NY its been oh about 10 degrees all day. I was able to get 24miles out of what the monitor showed 11.3kwh. How can this be? Now my 4yr old volt has been averaging 10.3 for the last few seasons which is expected after being 4 years old so degradation is great. But how is it possible to get 11.3 on such a cold day? Note I did preheat the volt for one iteration of 10 minutes or cycle. Is it possible the 11.3kwh includes the extra amountt consumed while plugged in and preheating/pre conditioning?
 

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Probably preheat while plugged in and it didnt charge fully?

Edit: I think that would show you using that electricity, and it will burn about 1 kw in 10 min at max power, so if it didn't quite charge up all the way to full after preheating it would mean you used a little more than a full charge. I get similar if I charge at lunch, but I haven't noticed with preheating, but I don't watch that closely.
 

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I’ve noticed with my 2015 that it will sometimes show 11.1 - 11.5 when ERDTT has happened on the drive. Perhaps the electricity generated by the engine confuses it?
 

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That's correct, that thing shows how much electricity is has been used since your last charge up until you switch to range extended (gas) mode.

If you've ever driven someplace, charged, and then unplugged before completing a full charge, you'll notice that it will keep going until you've used all of the electricity you added, so you'll get numbers like 14 or 15+ kwh

The same thing is true for ERDTT, since you're not technically in range extended mode, the electricity that the engine generated is added to the total.

Preheating does the same thing, specifically if you pull the plug prior to it completely topping off the battery. Again, the counter doesn't have the opportunity to reset itself.
 

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In ERDTT mode the electricity generated by gas is generally not added to the total (the car measures current in and out of the battery as far as I know, so is able to account for most of it generated by engine or not), although I think the accounting gets off sometimes. For example, my latest run with ERDTT showed this, my usual number is 9.4 kwh and this shows 9.2 kwh, so none of the electricity was added in (a whopping 29 MPGe or so):

20171228_084905 by Eric Tastad, on Flickr

I think the less trustworthy numbers are miles on gas and electric as those get accounted strangely in ERDTT mode in my 2012, especially if I put the car on "Fan only" climate with very cold temps (like single digits F or less). This is why I think the OP was credited with using some electricity that was recharged before he left, but not recharged all the way to reset the counter.

The fan only mode might cause the gauge to get off as the engine might run a lot more putting energy into the battery, but not sure, I think that just messes with your EV vs Gas miles, not so much the kwh used display.
 

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I think the less trustworthy numbers are miles on gas and electric as those get accounted strangely in ERDTT mode in my 2012, especially if I put the car on "Fan only" climate with very cold temps (like single digits F or less). This is why I think the OP was credited with using some electricity that was recharged before he left, but not recharged all the way to reset the counter.
Remember the 2011 and 2012 account for gas and electric miles differently from the rest of the Gen 1 line. Our experiences are not going to be seen by a 2014. We can, for example, creatively use Mountain Mode to trade poor MPG on the gas miles to get 100+ EV miles clocked on a single long drive without turning the car off.
 

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As mentioned, ERDTT can screw with it. It's not very good at keeping the two separate like it is when there's a full switchover.
Especially if you have had a slow drive to start and ERDTT managed to generate power over and above 'full', but not quite to the 'overfull' point.
Top-up charge as part of preconditioning is plausible, I suppose, but usually that accounts for the net, or reverses the counter if you are using <3kW.
e.g. if you used 1.2 kWh in heat while plugged in but charged 1kWh in that time, the display should read 0.2 or so.
 

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Discussion Starter #8
Probably preheat while plugged in and it didnt charge fully?

Edit: I think that would show you using that electricity, and it will burn about 1 kw in 10 min at max power, so if it didn't quite charge up all the way to full after preheating it would mean you used a little more than a full charge. I get similar if I charge at lunch, but I haven't noticed with preheating, but I don't watch that closely.
The car was already fully charged before i did at home preconditioning for 1 cycle before heading out.
 

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That's correct, that thing shows how much electricity is has been used since your last charge up until you switch to range extended (gas) mode.

If you've ever driven someplace, charged, and then unplugged before completing a full charge, you'll notice that it will keep going until you've used all of the electricity you added, so you'll get numbers like 14 or 15+ kwh

The same thing is true for ERDTT, since you're not technically in range extended mode, the electricity that the engine generated is added to the total.

Preheating does the same thing, specifically if you pull the plug prior to it completely topping off the battery. Again, the counter doesn't have the opportunity to reset itself.
Yes I have noticed that it is ever increasing if I never complete a 2nd charge and then drive showing accumulated battery usage.
 

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Discussion Starter #10
And today with similar cold day weather, the car showed 10.6 kwh used giving me about 26miles BUT this time I did not do preconditioning before leaving. Yes the carl was fully charged. Anyway interesting. For times like today especially unlike the day before with preconditioning, I don't expect the kwh to be higher than what seem to be the battery degraded value of 10.2kwh that was showing prior to this pretty much all year.
 

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I bought an used 2013 in September 2017. At the start I drove a lot of times to fully deplete the battery until the ICE kicked in as I did not have a plug in the garage. This is one photo of the battery used during one of those trips: https://1drv.ms/i/s!AvGfutWi2O0Rm_sO02JRBt-sIPYIsA and there was also about 1-2km left in the "tank".
See that I've used 11.1kWh of energy even thou my battery suppose to have 10.9 usable. And no ICE running in that cycle, 100% electric. This was done on a steady 60mph drive with almost no regeneration.

Maybe I do another fully depleting test when the weather gets better to see if I can reproduce the results.
 
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